Life Extension Magazine®

Issue: Feb 2010

Saw Palmetto

Scientifically reviewed by: Dr. Gary Gonzalez, MD, on January 2021.

Dietary strategies for improving post-prandial glucose, lipids, inflammation, and cardiovascular health.

The highly processed, calorie-dense, nutrient-depleted diet favored in the current American culture frequently leads to exaggerated supraphysiological post-prandial spikes in blood glucose and lipids. This state, called post-prandial dysmetabolism, induces immediate oxidant stress, which increases in direct proportion to the increases in glucose and triglycerides after a meal. The transient increase in free radicals acutely triggers atherogenic changes including inflammation, endothelial dysfunction, hypercoagulability, and sympathetic hyperactivity. Post-prandial dysmetabolism is an independent predictor of future cardiovascular events even in nondiabetic individuals. Improvements in diet exert profound and immediate favorable changes in the post-prandial dysmetabolism. Specifically, a diet high in minimally processed, high-fiber, plant-based foods such as vegetables and fruits, whole grains, legumes, and nuts will markedly blunt the post-meal increase in glucose, triglycerides, and inflammation. Additionally, lean protein, vinegar, fish oil, tea, cinnamon, calorie restriction, weight loss, exercise, and low-dose to moderate-dose alcohol each positively impact post-prandial dysmetabolism. Experimental and epidemiological studies indicate that eating patterns, such as the traditional Mediterranean or Okinawan diets, that incorporate these types of foods and beverages reduce inflammation and cardiovascular risk. This anti-inflammatory diet should be considered for the primary and secondary prevention of coronary artery disease and diabetes.

J Am Coll Cardiol. 2008 Jan 22;51(3):249-55

Resveratrol: biologic and therapeutic implications.

Resveratrol (3,4’,5 trihydroxystilbene), a naturally-occurring molecule known as a phytoalexin, is synthesized by plants in response to attacks by fungi, bacteria, or other injurious substances; it is also known to possess an array of cardioprotective effects. Recently, studies have shown resveratrol to protect against the metabolic changes associated with hypercaloric diets in mice with induced insulin resistance, hyperglycemia, and dyslipidemia. Despite impressive gains in diagnosis and treatment, cardiovascular disease (CVD) remains a serious clinical problem and threat to public health. The metabolic syndrome, which identifies persons at higher risk for diabetes mellitus and CVD, is approaching a prevalence of nearly 25% of the western world. If the metabolic syndrome can be considered a polar opposite to caloric restriction, then agents that mimic caloric restriction may offer a new therapeutic approach to preventing CVD. The authors discuss the cardioprotective effects of resveratrol and highlight its role in glucose homeostasis and lipid metabolism in mice. Armed with the ability to prevent the deleterious effects of excess caloric intake and prevent detrimental cardiovascular events, resveratrol merits proper clinical investigations for its efficacy in treating metabolic diseases and CVD.

J Cardiometab Syndr. 2009 Spring;4(2):102-6

Life extension by calorie restriction in humans.

Long-term reduction in energy intake in the diet (calorie restriction [CR]) extends the life of the laboratory rat by about 25%. However, in humans there are no life-long studies of CR, but only short-term trials which indicate that 20% CR acting over periods of 2-6 years is associated with reduced body weight, blood pressure, blood cholesterol, and blood glucose--risk factors for the major killer diseases of cardiovascular disease and diabetes. In addition, recent research has shown that CR for 6 months is able to improve biomarkers for longevity (deep body temperature and plasma insulin) and thus should increase life expectancy. The magnitude of the life-extension effect of CR in humans can only be estimated. The Okinawans, the longest-lived people on earth, consume 40% fewer calories than the Americans and live only 4 years longer. Similarly, women in United States consume 25% fewer calories than men and live 5 years longer. From the survival studies of overweight and obese people, it is estimated that long-term CR to prevent excessive weight gain could add only 3-13 years to life expectancy. Thus the effects of CR on human life extension are probably much smaller than those achieved by medical and public health interventions, which have extended life by about 30 years in developed countries in the 20th century, by greatly reducing deaths from infections, accidents, and cardiovascular disease.

Ann N Y Acad Sci. 2007 Oct;1114:428-33

Effect of 6-month calorie restriction on biomarkers of longevity, metabolic adaptation, and oxidative stress in overweight individuals: a randomized controlled trial.

CONTEXT: Prolonged calorie restriction increases life span in rodents. Whether prolonged calorie restriction affects biomarkers of longevity or markers of oxidative stress, or reduces metabolic rate beyond that expected from reduced metabolic mass, has not been investigated in humans. OBJECTIVE: To examine the effects of 6 months of calorie restriction, with or without exercise, in overweight, nonobese (body mass index, 25 to <30) men and women. DESIGN, SETTING, AND PARTICIPANTS: Randomized controlled trial of healthy, sedentary men and women (N = 48) conducted between March 2002 and August 2004 at a research center in Baton Rouge, La. INTERVENTION: Participants were randomized to 1 of 4 groups for 6 months: control (weight maintenance diet); calorie restriction (25% calorie restriction of baseline energy requirements); calorie restriction with exercise (12.5% calorie restriction plus 12.5% increase in energy expenditure by structured exercise); very low-calorie diet (890 kcal/d until 15% weight reduction, followed by a weight maintenance diet). MAIN OUTCOME MEASURES: Body composition; dehydroepiandrosterone sulfate (DHEAS), glucose, and insulin levels; protein carbonyls; DNA damage; 24-hour energy expenditure; and core body temperature. RESULTS: Mean (SEM) weight change at 6 months in the 4 groups was as follows: controls, -1.0% (1.1%); calorie restriction, -10.4% (0.9%); calorie restriction with exercise, -10.0% (0.8%); and very low-calorie diet, -13.9% (0.7%). At 6 months, fasting insulin levels were significantly reduced from baseline in the intervention groups (all P<.01), whereas DHEAS and glucose levels were unchanged. Core body temperature was reduced in the calorie restriction and calorie restriction with exercise groups (both P<.05). After adjustment for changes in body composition, sedentary 24-hour energy expenditure was unchanged in controls, but decreased in the calorie restriction (-135 kcal/d [42 kcal/d]), calorie restriction with exercise (-117 kcal/d [52 kcal/d]), and very low-calorie diet (-125 kcal/d [35 kcal/d]) groups (all P<.008). These “metabolic adaptations” (~ 6% more than expected based on loss of metabolic mass) were statistically different from controls (P<.05). Protein carbonyl concentrations were not changed from baseline to month 6 in any group, whereas DNA damage was also reduced from baseline in all intervention groups (P <.005). CONCLUSIONS: Our findings suggest that 2 biomarkers of longevity (fasting insulin level and body temperature) are decreased by prolonged calorie restriction in humans and support the theory that metabolic rate is reduced beyond the level expected from reduced metabolic body mass. Studies of longer duration are required to determine if calorie restriction attenuates the aging process in humans. TRIAL REGISTRATION: Identifier: NCT00099151.

JAMA. 2006 Apr 5;295(13):1539-48

Caloric restriction in humans.

Studies on mice and rats have demonstrated that calorie restriction (CR) slows primary aging, has a protective effect against secondary aging, and markedly decreases the incidence of malignancies. However, the only way to determine whether CR “works” in humans is to conduct studies on people. Such studies are difficult to perform in free-living people. While research on CR in humans is still at an early stage, a modest amount of information has accumulated. Because it is not feasible to conduct studies of the effects of CR on longevity in humans, surrogate measures have to be used. Preliminary information obtained using this approach provides evidence that CR provides a powerful protective effect against secondary aging in humans. This evidence consists of the finding that risk factors for atherosclerosis and diabetes are markedly reduced in humans on CR. Humans on CR also show some of the same adaptations that are thought to be involved in slowing primary aging in rats and mice. These include a very low level of inflammation as evidenced by low circulating levels of C-reactive protein and TNFalpha, serum triiodothyronine levels at the low end of the normal range, and a more elastic “younger” left ventricle (LV), as evaluated by echo-doppler measures of LV stiffness.

Exp Gerontol. 2007 Aug;42(8):709-12

Calorie restriction increases muscle mitochondrial biogenesis in healthy humans.

BACKGROUND: Caloric restriction without malnutrition extends life span in a range of organisms including insects and mammals and lowers free radical production by the mitochondria. However, the mechanism responsible for this adaptation are poorly understood. METHODS AND FINDINGS: The current study was undertaken to examine muscle mitochondrial bioenergetics in response to caloric restriction alone or in combination with exercise in 36 young (36.8 +/- 1.0 y), overweight (body mass index, 27.8 +/- 0.7 kg/m(2)) individuals randomized into one of three groups for a 6-mo intervention: Control, 100% of energy requirements; CR, 25% caloric restriction; and CREX, caloric restriction with exercise (CREX), 12.5% CR + 12.5% increased energy expenditure (EE). In the controls, 24-h EE was unchanged, but in CR and CREX it was significantly reduced from baseline even after adjustment for the loss of metabolic mass (CR, -135 +/- 42 kcal/d, p = 0.002 and CREX, -117 +/- 52 kcal/d, p = 0.008). Participants in the CR and CREX groups had increased expression of genes encoding proteins involved in mitochondrial function such as PPARGC1A, TFAM, eNOS, SIRT1, and PARL (all, p < 0.05). In parallel, mitochondrial DNA content increased by 35% +/- 5% in the CR group (p = 0.005) and 21% +/- 4% in the CREX group (p < 0.004), with no change in the control group (2% +/- 2%). However, the activity of key mitochondrial enzymes of the TCA (tricarboxylic acid) cycle (citrate synthase), beta-oxidation (beta-hydroxyacyl-CoA dehydrogenase), and electron transport chain (cytochrome C oxidase II) was unchanged. DNA damage was reduced from baseline in the CR (-0.56 +/- 0.11 arbitrary units, p = 0.003) and CREX (-0.45 +/- 0.12 arbitrary units, p = 0.011), but not in the controls. In primary cultures of human myotubes, a nitric oxide donor (mimicking eNOS signaling) induced mitochondrial biogenesis but failed to induce SIRT1 protein expression, suggesting that additional factors may regulate SIRT1 content during CR. CONCLUSIONS: The observed increase in muscle mitochondrial DNA in association with a decrease in whole body oxygen consumption and DNA damage suggests that caloric restriction improves mitochondrial function in young non-obese adults.

PLoS Med. 2007 Mar;4(3):e76

Caloric restriction in primates.

Caloric restriction (CR) remains the only nongenetic intervention that reproducibly extends mean and maximal life span in short-lived mammalian species. This nutritional intervention also delays the onset, or slows the progression, of many age-related disease processes. The diverse effects of CR have been demonstrated many hundreds of times in laboratory rodents and other short-lived species, such as rotifers, water fleas, fish, spiders, and hamsters. Until recently, the effects of CR in longer-lived species, more closely related to humans, remained unknown. Long-term studies of aging in nonhuman primates undergoing CR have been underway at the National Institute on Aging (NIA) and the University of Wisconsin-Madison (UW) for over a decade. A number of reports from the NIA and UW colonies have shown that monkeys on CR exhibit nearly identical physiological responses as reported in laboratory rodents. Studies of various markers related to age-related diseases suggest that CR will prevent or delay the onset of cardiovascular disease, diabetes, and perhaps cancer, and preliminary data indicate that mortality due to these and other age-associated diseases may also be reduced in monkeys on CR, compared to controls. Conclusive evidence showing that CR extends life span in primates is not presently available; however, the emerging data from the ongoing primate studies strengthens the possibility that the diverse beneficial effects of CR on aging in rodents will also apply to nonhuman primates and perhaps ultimately to humans.

Ann N Y Acad Sci. 2001 Apr;928:287-95

Caloric restriction in primates and relevance to humans.

Dietary caloric restriction (CR) is the only intervention conclusively and reproducibly shown to slow aging and maintain health and vitality in mammals. Although this paradigm has been known for over 60 years, its precise biological mechanisms and applicability to humans remain unknown. We began addressing the latter question in 1987 with the first controlled study of CR in primates (rhesus and squirrel monkeys, which are evolutionarily much closer to humans than the rodents most frequently employed in CR studies). To date, our results strongly suggest that the same beneficial “antiaging” and/or “antidisease” effects observed in CR rodents also occur in primates. These include lower plasma insulin levels and greater sensitivity; lower body temperatures; reduced cholesterol, triglycerides, blood pressure, and arterial stiffness; elevated HDL; and slower age-related decline in circulating levels of DHEAS. Collectively, these biomarkers suggest that CR primates will be less likely to incur diabetes, cardiovascular problems, and other age-related diseases and may in fact be aging more slowly than fully fed counterparts. Despite these very encouraging results, it is unlikely that most humans would be willing to maintain a 30% reduced diet for the bulk of their adult life span, even if it meant more healthy years. For this reason, we have begun to explore CR mimetics, agents that might elicit the same beneficial effects as CR, without the necessity of dieting. Our initial studies have focused on 2-deoxyglucose (2DG), a sugar analogue with a limited metabolism that actually reduces glucose/energy flux without decreasing food intake in rats. In a six-month pilot study, 2DG lowered plasma insulin and body temperature in a manner analagous to that of CR. Thus, metabolic effects that mediate the CR mechanism can be attained pharmacologically. Doses were titrated to eliminate toxicity; a long-term longevity study is now under way. In addition, data from other laboratories suggest that at least some of the same physiological/metabolic end points that are associated with the beneficial effects of underfeeding may be obtained from other potential CR mimetic agents, some naturally occurring in food products. Much work remains to be done, but taken together, our successful results with CR in primates and 2DG administration to rats suggest that it may indeed be possible to obtain the health- and longevity-promoting effects of the former intervention without actually decreasing food intake.

Ann N Y Acad Sci. 2001 Apr;928:305-15

Calorie restriction attenuates inflammatory responses to myocardial ischemia-reperfusion injury.

The life-prolonging effects of calorie restriction (CR) may be due to reduced damage from cumulative oxidative stress. Our goal was to determine the long-term effects of moderate dietary CR on the myocardial response to reperfusion after a single episode of sublethal ischemia. Male Fisher 344 rats were fed either an ad libitum (AL) or CR (40% less calories) diet. At age 12 mo the animals were anaesthetized and subjected to thoracotomy and a 15-min left-anterior descending coronary artery occlusion. The hearts were reperfused for various periods. GSH and GSSG levels, nuclear factor-kappaB (NF-kappaB) DNA binding activity, cytokine, and antioxidant enzyme expression were assessed in the ischemic zones. Sham-operated animals served as controls. Compared with the AL diet, chronic CR limited oxidative stress as seen by rapid recovery in GSH levels in previously ischemic myocardium. CR reduced DNA binding activity of NF-kappaB. The kappaB-responsive cytokines interleukin-1beta and tumor necrosis factor-alpha were transiently expressed in the CR group but persisted longer in the AL group. Furthermore, expression of manganese superoxide dismutase, a key antioxidant enzyme, was significantly delayed in the AL group. Collectively these data indicate that CR significantly attenuates myocardial oxidative stress and the postischemic inflammatory response.

Am J Physiol Heart Circ Physiol. 2001 May;280(5):H2094-102

Molecular inflammation hypothesis of aging based on the anti-aging mechanism of calorie restriction.

Accumulating evidence strongly suggests that oxidative stress underlies aging processes. Research provides consistent evidence that calorie restriction (CR) reduces age-related oxidative stress and has anti-inflammatory properties. However, information is lacking on the molecular mechanism that would better define the interrelation of reactive oxygen species and nitrogen species and the pro-inflammatory states of the aging process. In this review, the biochemical and molecular bases of the inflammatory process in the aging process are analyzed to delineate the molecular inflammation hypothesis of aging. The key players involved in the proposed hypothesis are the age-related upregulation of NF-kappa B, IL-1 beta, IL-6, TNFalpha, cyclooxygenase-2, and inducible NO synthase, all of which are attenuated by CR. Furthermore, age-related NF kappa B activation is associated with phosphorylation by I kappa B kinase/NIK and MAPKs, while CR blocked these activation processes. The modulation of these factors provides molecular insights of the anti-inflammatory action of CR in relation to the aging process. Based on available finding and our recent supporting evidence, we prefer to use “molecular inflammation” to emphasize the importance of the molecular reaction mechanisms and their aberrance, predisposing to fully expressed chronic inflammatory phenomena. It was further proposed that CR’s major force of the regulation of redox-sensitive inflammation may well be its life-prolonging action.

Microsc Res Tech. 2002 Nov 15;59(4):264-72

The inflammation hypothesis of aging: molecular modulation by calorie restriction.

Current evidence strongly indicates that reactive oxygen species (ROS) and reactive nitrogen species (RNS) are widely implicated in the inflammatory process. However, mechanistic information is not readily available on the extent to which ROS/RNS contributes to the proinflammatory states of the aging process. The involvement of the underlying inflammation during the aging process and the molecular delineation of anti-inflammatory action of calorie restriction (CR) is described. Age-related upregulations of NF-kappaB, IL-beta, IL-6, TNFalpha, cyclooxygenase-2, and inducible NO synthase are all attenuated by CR. The suppression of the NF-kappaB activation was accomplished by blocking the dissociation of inhibitory IkappaBalpha and IkappaBbeta by CR. These findings provide underlying molecular insights into the anti-inflammatory action of CR in relation to the aging process. Based on these and other available data, it is suggested that the “Inflammation Hypothesis of Aging” supports the molecular basis of the inflammatory process as a plausible cause of the aging process.

Ann N Y Acad Sci. 2001 Apr;928:327-35

The use of a Cissus quadrangularis/Irvingia gabonensis combination in the management of weight loss: a double-blind placebo-controlled study.

AIM: To evaluate the effects of two formulations, Cissus quadrangularis-only and a Cissus quadrangularis/Irvingia gabonensis combination, on weight loss in overweight and obese human subjects. METHODS: The study was a 10 week randomized, double-blind, placebo-controlled design involving 72 obese or overweight participants (45.8% male; 54.2% female; ages 21-44; mean age = 29.3). The participants were randomly divided into three equal (n = 24) groups: placebo, Cissus quadrangularis-only, and Cissus quadrangularis/Irvingia gabonensis combination. Capsules containing the placebo or active formulations were administered twice daily before meals; no major dietary changes nor exercises were suggested during the study. A total of six anthropomorphic and serological measurements (body weight, body fat, waist size; total plasma cholesterol, LDL cholesterol, fasting blood glucose level) were taken at baseline and at 4, 8 and 10 weeks. RESULTS: Compared to the placebo group, the two active groups showed a statistically significant difference on all six variables by week 10. The magnitude of the differences was noticeable by week 4 and continued to increase over the trial period. CONCLUSION: Although the Cissus quadrangularis-only group showed significant reductions on all variables compared to the placebo group, the Cissus quadrangularis/Irvingia gabonensis combination resulted in even larger reductions. This apparently synergistic formulation should prove helpful in the management of obesity and its related complications.

Lipids Health Dis. 2008 Mar 31;7:12

IGOB131, a novel seed extract of the West African plant Irvingia gabonensis, significantly reduces body weight and improves metabolic parameters in overweight humans in a randomized double-blind placebo controlled investigation.

BACKGROUND: A recent in vitro study indicates that IGOB131, a novel seed extract of the traditional West African food plant Irvingia gabonensis, favorably impacts adipogenesis through a variety of critical metabolic pathways including PPAR gamma, leptin, adiponectin, and glycerol-3 phosphate dehydrogenase. This study was therefore aimed at evaluating the effects of IGOB131, an extract of Irvingia gabonensis, on body weight and associated metabolic parameters in overweight human volunteers. METHODS: The study participants comprised of 102 healthy, overweight and/or obese volunteers (defined as BMI > 25 kg/m2) randomly divided into two groups. The groups received on a daily basis, either 150 mg of IGOB131 or matching placebo in a double blinded fashion, 30-60 minutes before lunch and dinner. At baseline, 4, 8 and 10 weeks of the study, subjects were evaluated for changes in anthropometrics and metabolic parameters to include fasting lipids, blood glucose, C-reactive protein, adiponectin, and leptin. RESULTS: Significant improvements in body weight, body fat, and waist circumference as well as plasma total cholesterol, LDL cholesterol, blood glucose, C-reactive protein, adiponectin and leptin levels were observed in the IGOB131 group compared with the placebo group. CONCLUSION: Irvingia gabonensis administered 150 mg twice daily before meals to overweight and/or obese human volunteers favorably impacts body weight and a variety of parameters characteristic of the metabolic syndrome. This is the first double blind randomized placebo controlled clinical trial regarding the anti-obesity and lipid profile modulating effects of an Irvingia gabonensis extract. The positive clinical results, together with our previously published mechanisms of gene expression modulation related to key metabolic pathways in lipid metabolism, provide impetus for much larger clinical studies. Irvingia gabonensis extract may prove to be a useful tool in dealing with the emerging global epidemics of obesity, hyperlipidemia, insulin resistance, and their co-morbid conditions.

Lipids Health Dis. 2009 Mar 2;8:7

Inhibition of Irvingia gabonensis seed extract (OB131) on adipogenesis as mediated via down regulation of the PPARgamma and leptin genes and up-regulation of the adiponectin gene.

BACKGROUND: Endeavors to manage obesity have been heavily reliant on controlling energy intake and expenditure equilibrium, but have failed to curtail the overweight and obesity epidemic. This dynamic equilibrium is more complex than originally postulated and is influenced by lifestyle, calorie and nutrient intake, reward cravings and satiation, energy metabolism, stress response capabilities, immune metabolism and genetics. Fat metabolism is an important indicator of how efficiently and to what extent these factors are competently integrating. We investigated whether an Irvingia gabonensis seed extract (IGOB131) would provide a more beneficial comprehensive approach influencing multiple mechanisms and specifically PPAR gamma, leptin and adiponectin gene expressions, important in anti-obesity strategies. METHODS: Using murine 3T3-L1 adipocytes as a model for adipose cell biology research, the effects of IGOB131 were investigated on PPAR gamma, adiponectin, and leptin. These adipocytes were harvested 8 days after the initiation of differentiation and treated with 0 to 250 microM of IGOB131 for 12 and 24 h at 37 degree C in a humidified 5 percent CO2 incubator. The relative expression of PPAR gamma, adiponectin, and leptin in 3T3-L1 adipocytes was quantified densitometrically using the software LabWorks 4.5, and calculated according to the reference bands of beta-actin. RESULTS: The IGOB131 significantly inhibited adipogenesis in adipocytes. The effect appears to be mediated through the down-regulated expression of adipogenic transcription factors (PPAR gamma) [P less than 0.05] and adipocyte-specific proteins (leptin) [P less than 0.05], and by up-regulated expression of adiponectin [P less than 0.05]. CONCLUSION: IGOB131 may play an important multifaceted role in the control of adipogenesis and have further implications in in-vivo anti obesity effects by targeting the PPAR gamma gene, a known contributory factor to obesity in humans.

Lipids Health Dis. 2008 Nov 13;7:44

Adiponectin is a link among inflammation, insulin resistance, and high-density lipoprotein cholesterol but is not associated with paraoxonase activity in premenopausal women.

The aim of this study was to evaluate whether insulin sensitivity, inflammatory response, and plasma lipid profile are associated with circulating adiponectin levels in nondiabetic healthy women. The authors also assessed whether adiponectin has any effect on high-density lipoprotein cholesterol-linked paraoxonase 1 (PON-1) activity and on the susceptibility of low-density lipoproteins to oxidation. Plasma adiponectin was measured in 91 nondiabetic premenopausal women, and the patients were then divided into quartiles. Circulating adiponectin was found to be associated with body mass index (r=.55, P<.001). After adjustment for body mass index, adiponectin showed an inverse correlation with the homeostasis model assessment of insulin resistance (HOMA-IR) (r=-.41, P<.001) and a positive correlation with high-density lipoprotein cholesterol (r=.43, P<.001). In linear regression analysis, HOMA-IR, tumor necrosis factor alpha, and high-density lipoprotein cholesterol levels were found to be independently associated with adiponectin. However, high-density lipoprotein cholesterol-linked PON-1 activity and the susceptibility of low-density lipoproteins to in vitro oxidation did not seem to be related to plasma adiponectin concentrations.

J Clin Hypertens (Greenwich). 2009 Nov;11(11):672-7

Effects of long-term calorie restriction and endurance exercise on glucose tolerance, insulin action, and adipokine production.

Calorie restriction (CR) slows aging and is thought to improve insulin sensitivity in laboratory animals. In contrast, decreased insulin signaling and/or mild insulin resistance paradoxically extends maximal lifespan in various genetic animal models of longevity. Nothing is known regarding the long-term effects of CR on glucose tolerance and insulin action in lean healthy humans. In this study we evaluated body composition, glucose, and insulin responses to an oral glucose tolerance test and serum adipokines levels in 28 volunteers, who had been eating a CR diet for an average of 6.9 +/- 5.5 years, (mean age 53.0 +/- 11 years), in 28 age-, sex-, and body fat-matched endurance runners (EX), and 28 age- and sex-matched sedentary controls eating Western diets (WD). We found that the CR and EX volunteers were significantly leaner than the WD volunteers. Insulin sensitivity, determined according to the HOMA-IR and the Matsuda and DeFronzo insulin sensitivity indexes, was significantly higher in the CR and EX groups than in the WD group (P = 0.001). Nonetheless, despite high serum adiponectin and low inflammation, approximately 40% of CR individuals exhibited an exaggerated hyperglycemic response to a glucose load. This impaired glucose tolerance is associated with lower circulating levels of IGF-1, total testosterone, and triiodothyronine, which are typical adaptations to life-extending CR in rodents.

Age (Dordr). 2009 Nov 11

Adipocytokines and the metabolic syndrome among older persons with and without obesity - the InCHIANTI Study.

SUMMARY Objective: Adipose tissue-derived inflammation may contribute to metabolic alterations and eventually to the metabolic syndrome (MetS). The purpose of this study was to: 1) examine the role of adipocytokines in the association between obesity and the MetS; and 2) to determine whether the association is different in obese and non-obese persons. Design: Cross-sectional population-based InCHIANTI study. Subjects: 944 community-dwelling adults aged 65 years and older living in Tuscany, Italy. Measurements: Obesity was defined as body mass index >/= 30 kg/m(2) and MetS as >/= 3 of the ATP-III criteria. Circulating levels of CRP, IL-6, IL-1ra, IL-18, TNF-alpha R1, adiponectin, resistin, and leptin were measured. Additionally, insulin resistance was determined using the homeostasis model assessment (HOMA-IR). Results: The prevalence of the MetS was 32%. Both overall and abdominal obesity were significantly associated with the MetS after adjusting for inflammatory cytokines, adipokines and lifestyle factors. After adjusting for multiple confounders and HOMA-IR, IL-1ra, TNF-alpha R1 and adiponectin (p < 0.05) remained significantly associated with the MetS. Having multiple cytokines in the highest tertile increased the likelihood of having the MetS in both obese (p for trend 0.002) and non-obese persons (p for trend 0.001) independent of insulin resistance. Conclusions: Non-obese and obese individuals who develop an intense pro-inflammatory state may be more prone to develop the MetS than those with lower levels of inflammation.

Clin Endocrinol (Oxf). 2009 Oct 31

Antidiabetic and antioxidant effects of polyphenols in brown alga Ecklonia stolonifera in genetically diabetic KK-A(y) mice.

The dietary intake and control of blood glucose levels are very important in hyperglycemic patients and alpha-glucosidase inhibitors are a cost-effective means to preventing the progression of diabetes. In search of a natural inhibitor from food materials, alpha-glucosidase inhibitory activity and the anti-hyperglycemic effects of a brown alga, Ecklonia stolonifera, were investigated using non-insulin dependent diabetic mice. Methanolic extract of E. stolonifera (MEE), which contains a high content of polyphenols, showed strong inhibition of alpha-glucosidase in vitro. Male KK-A(y) mice, a genetically non-insulin dependent diabetic model, showed hyperglycemia with aging, but the ingestion of MEE suppressed the increase in plasma glucose and lipid peroxidation levels in unfasted KK-A(y) mice dose dependently. In KK-A(y) mice, which were fed the MEE diet for 4 weeks, MEE moderated the elevation of plasma glucose levels after the oral administration of maltose. The polyphenols in MEE were estimated to be phlorotannins by HPLC-PDA and LC/MS analyses. These results demonstrate that E. stolonifera, seaweed typically used as a health food, has strong antidiabetic and antioxidant effects in vivo, thus, it may have beneficial properties in the prevention of diabetes and could be useful in the development of an antidiabetic pharmaceutical and functional food.

Plant Foods Hum Nutr. 2008 Dec;63(4):163-9

Hypoglycemic activity of several seaweed extracts.

The hypoglycemic activity of several seaweed extracts on rabbits was studied. Ethanol extracts of Laminaria ochroleuca, Saccorhiza polyschides and Fucus vesiculosus were administered orally to normal animals and their effects on glycemia and triglyceridemia evaluated. Crude polysaccharides and protein solutions from Himanthalia elongata and Codium tomentosum were also assayed. Polysaccharides and proteins from H. elongata caused a significant reduction in blood glucose 8 h after intravenous administration. A case of 5 mg/kg of crude polysaccharide lowered glycemia about 18% in normal rabbits and by about 50% in alloxan-diabetic animals, while the protein solution lowered glycemia in diabetic rabbits by about 30%.

J Ethnopharmacol. 1989 Nov;27(1-2):35-43

Antidiabetic properties of polysaccharide- and polyphenolic-enriched fractions from the brown seaweed Ascophyllum nodosum.

We screened seaweed species from Atlantic Canada for antidiabetic activity by testing extracts for alpha-glucosidase inhibitory effect and glucose uptake stimulatory activity. An aqueous ethanolic extract of Ascophyllum nodosum was found to be active in both assays, inhibiting rat intestinal alpha-glucosidase (IC50 = 77 microg/mL) and stimulating basal glucose uptake into 3T3-L1 adipocytes during a 20-minute incubation by about 3-fold (at 400 microg/mL extract). Bioassay-guided fractionation of the A. nodosum extract showed that alpha-glucosidase inhibition was associated with polyphenolic components in the extract. These polyphenolics, along with other constituents appeared to be responsible for the stimulatory activity on glucose uptake. However, attempts to further concentrate this activity through fractionation techniques were unsuccessful. A crude polyphenol extract (PPE), an enriched polyphenolic fraction (PPE-F1) and a polysaccharide extract (PSE) were prepared from commercial A. nodosum powder and administered to streptozotocin-diabetic mice for up to 4-weeks by daily gavage at 200 mg/kg body mass. PPE and PPE-F1 improved fasting serum glucose level in diabetic mice; however, the effect was only statistically significant at day 14. In addition, PPE-F1 was shown to blunt the rise in blood glucose after an oral sucrose tolerance test in diabetic mice. Mice treated with PPE and PPE-F1 had decreased blood total cholesterol and glycated serum protein levels compared with untreated diabetic mice, whereas PPE also normalized the reduction in liver glycogen level that occurred in diabetic animals. All 3 A. nodosum preparations improved blood antioxidant capacity.

Can J Physiol Pharmacol. 2007 Nov;85(11):1116-23

Lipid-lowering treatment in metabolic syndrome.

During the last decades, metabolic syndrome has become an important healthcare problem worldwide. Main components of metabolic syndrome are insulin resistance (resulting often in impaired glucose tolerance and diabetes mellitus), dyslipidemia, hypertension and abdominal obesity. Incidence of metabolic syndrome is high and it substantially increases the risk of cardiovascular diseases. Dyslipidemia is a prominent factor contributing to the increased cardiovascular risk in metabolic syndrome, and lipid-lowerign therapy plays an important role in treating patients with this disorder. Most patients with dyslipidemia are treated with statins and/or fibrates. Statins are used for treatment of hypercholesterolemia; fibrates are indicated for treatment of hypertriglyceridemia and/or low HDL-cholesterol. In high risk patients with severe mixed hyperlipidemia, combination ofstatins with fibrates may be necessary to achieve the lipid goals.

Vnitr Lek. 2009 Jul-Aug;55(7-8):626-30

Mitochondrial function, fibre types and ageing: new insights from human muscle in vivo.

Mitochondrial changes are at the centre of a wide range of maladies, including diabetes, neurodegeneration and ageing-related dysfunctions. Here we describe innovative optical and magnetic resonance spectroscopic methods that non-invasively measure key mitochondrial fluxes, ATP synthesis and O(2) uptake, to permit the determination of mitochondrial coupling efficiency in vivo (P/O: half the ratio of ATP flux to O(2) uptake). Three new insights result. First, mitochondrial coupling can be measured in vivo with the rigor of a biochemical determination and provides a gold standard to define well-coupled mitochondria (P/O approximately 2.5). Second, mitochondrial coupling differs substantially among muscles in healthy adults, from values reflective of well-coupled oxidative phosphorylation in a hand muscle (P/O = 2.7) to mild uncoupling in a leg muscle (P/O = 2.0). Third, these coupling differences have an important impact on cell ageing. We found substantial uncoupling and loss of cellular [ATP] in a hand muscle indicative of mitochondrial dysfunction with age. In contrast, stable mitochondrial function was found in a leg muscle, which supports the notion that mild uncoupling is protective against mitochondrial damage with age. Thus, greater mitochondrial dysfunction is evident in muscles with higher type II muscle fibre content, which may be at the root of the preferential loss of type II fibres found in the elderly. Our results demonstrate that mitochondrial function and the tempo of ageing varies among human muscles in the same individual. These technical advances, in combination with the range of mitochondrial properties available in human muscles, provide an ideal system for studying mitochondrial function in normal tissue and the link between mitochondrial defects and cell pathology in disease.

Exp Physiol. 2007 Mar;92(2):333-9

Mitochondrial dysfunction in cardiac disease: ischemia—reperfusion, aging, and heart failure.

Mitochondria contribute to cardiac dysfunction and myocyte injury via a loss of metabolic capacity and by the production and release of toxic products. This article discusses aspects of mitochondrial structure and metabolism that are pertinent to the role of mitochondria in cardiac disease. Generalized mechanisms of mitochondrial-derived myocyte injury are also discussed, as are the strengths and weaknesses of experimental models used to study the contribution of mitochondria to cardiac injury. Finally, the involvement of mitochondria in the pathogenesis of specific cardiac disease states (ischemia, reperfusion, aging, ischemic preconditioning, and cardiomyopathy) is addressed.

Mol Cell Cardiol. 2001 Jun;33(6):1065-89

Mitochondrial dysfunction and age.

PURPOSE OF REVIEW: Mito-chondrial dysfunction is commonly thought to result from oxidative damage that leads to defects in the electron transport chain (ETC). In this review, we highlight new research indicating that there are early changes in mitochondrial function that precede ETC defects and are reversible thereby providing the possibility of slowing the tempo of mitochondrial aging and cell death. RECENT FINDINGS: Increased mitochondrial uncoupling - reduced adenosine triphosphate (ATP) produced per O2 uptake - and cell ATP depletion are evident in human muscle nearly a decade before accumulation of irreversible DNA damage that causes ETC defects. New evidence points to reduction in activators of biogenesis (e.g. PGC-1alpha) and to degradation of mitochondria allowing accumulation of molecular and membrane damage in aged mitochondria. The early dysfunction appears to be reversible based on improved mitochondrial function in vivo and elevated gene expression levels after exercise training. SUMMARY: New molecular and in vivo findings regarding the onset and reversibility of mitochondrial dysfunction with age indicate the potential: 1) for diagnostic tools to identify patients at risk for severe irreversible defects later in life; and 2) of an intervention to delay the tempo of aging and improve the quality of life of the elderly.

Curr Opin Clin Nutr Metab Care. 2007 Nov;10(6):688-92

(R)-alpha-lipoic acid-supplemented old rats have improved mitochondrial function, decreased oxidative damage, and increased metabolic rate.

A diet supplemented with (R)-lipoic acid, a mitochondrial coenzyme, was fed to old rats to determine its efficacy in reversing the decline in metabolism seen with age. Young (3 to 5 months) and old (24 to 26 months) rats were fed an AIN-93M diet with or without (R)-lipoic acid (0.5% w/w) for 2 wk, killed, and their liver parenchymal cells were isolated. Hepatocytes from untreated old rats vs. young controls had significantly lower oxygen consumption (P<0. 03) and mitochondrial membrane potential. (R)-Lipoic acid supplementation reversed the age-related decline in O2 consumption and increased (P<0.03) mitochondrial membrane potential. Ambulatory activity, a measure of general metabolic activity, was almost threefold lower in untreated old rats vs. controls, but this decline was reversed (P<0.005) in old rats fed (R)-lipoic acid. The increase of oxidants with age, as measured by the fluorescence produced on oxidizing 2’,7’-dichlorofluorescin, was significantly lowered in (R)-lipoic acid supplemented old rats (P<0.01). Malondialdehyde (MDA) levels, an indicator of lipid peroxidation, were increased fivefold with age in cells from unsupplemented rats. Feeding rats the (R)-lipoic acid diet reduced MDA levels markedly (P<0.01). Both glutathione and ascorbic acid levels declined in hepatocytes with age, but their loss was completely reversed with (R)-lipoic acid supplementation. Thus, (R)-lipoic acid supplementation improves indices of metabolic activity as well as lowers oxidative stress and damage evident in aging.

FASEB J. 1999 Feb;13(2):411-8

Oxidative damage and mitochondrial decay in aging.

We argue for the critical role of oxidative damage in causing the mitochondrial dysfunction of aging. Oxidants generated by mitochondria appear to be the major source of the oxidative lesions that accumulate with age. Several mitochondrial functions decline with age. The contributing factors include the intrinsic rate of proton leakage across the inner mitochondrial membrane (a correlate of oxidant formation), decreased membrane fluidity, and decreased levels and function of cardiolipin, which supports the function of many of the proteins of the inner mitochondrial membrane. Acetyl-L-carnitine, a high-energy mitochondrial substrate, appears to reverse many age-associated deficits in cellular function, in part by increasing cellular ATP production. Such evidence supports the suggestion that age-associated accumulation of mitochondrial deficits due to oxidative damage is likely to be a major contributor to cellular, tissue, and organismal aging.

Proc Natl Acad Sci U S A. 1994 Nov 8;91(23):10771-8

Mitochondrial decay in hepatocytes from old rats: membrane potential declines, heterogeneity and oxidants increase.

Mitochondrial function during aging was assessed in isolated rat hepatocytes to avoid the problem of differential lysis when old, fragile mitochondria are isolated. Rhodamine 123, a fluorescent dye that accumulates in mitochondria on the basis of their membrane potential, was used as a probe to determine whether this key function is affected by aging. A marked fluorescent heterogeneity was observed in hepatocytes from old (20-28 months) but not young (3-5 months) rats, suggesting age-associated alterations in mitochondrial membrane potential, the driving force for ATP synthesis. Three distinct cell subpopulations were separated by centrifugal elutriation; each exhibited a unique rhodamine 123 fluorescence pattern, with the largest population from old rats having significantly lower fluorescence than that seen in young rats. This apparent age-associated alteration in mitochondrial membrane potential was confirmed by measurements with radioactive tetraphenylphosphonium bromide. Cells from young rats had a calculated membrane potential of -154 mV, in contrast to that of the three subpopulations from old rats of -70 mV (the largest population), -93 mV, and -154 mV. Production of oxidants was examined using 2’,7’dichlorofluorescin, a dye that forms a fluorescent product upon oxidation. The largest cell subpopulation and a minor one from old animals produced significantly more oxidants than cells from young rats. To investigate the molecular cause(s) for the heterogeneity, we determined the levels of an age-associated mtDNA deletion. No significant differences were seen in the three subpopulations, indicating that the mitochondrial decay is due to other mutations, epigenetic changes, or both.

Proc Natl Acad Sci U S A. 1997 Apr 1;94(7):3064-9

Age-dependent modifications in rat hepatocyte antioxidant defense systems.

BACKGROUND/AIMS: Age-dependent changes in the hepatic antioxidant systems were studied in hepatocytes from newly weaned (21 days) to 30-month-old rats. RESULTS: Biphasic changes were observed in superoxide dismutase (SOD), glucose-6-phosphate dehydrogenase (G6PDH) and malic enzyme (ME), in which noticeable decreases were detected in hepatocytes from newly weaned to 6-month-old rats: Cu-Zn SOD decreased to 46% (p < 0.001), Mn SOD to 41% (p < 0.001), G6PDH to 71% and ME to 19% (p < 0,001), and significant increases were observed from 6 to 30 months. In hepatocytes from 6- to 30- month-old rats the enzymes involved in antioxidant defense underwent increases in their activities as well in their mRNA: Cu-Zn SOD (142%, p < 0.001), catalase (182%, p < 0.001) and glutathione peroxidase (325%, p < 0.001). However, chronological decreases were observed in the levels of reduced glutathione (69%, p < 0.001), in the GSH/GSSG ratio (78%) and in protein thiol groups (55%, p < 0.001), with concomitant increases in peroxides (155%, p < 0.001) and malondialdehyde (142%, p < 0.001) levels. DNA ploidy was also assayed by flow cytometry; a sharp increase in tetraploid (2.5-40.1%, p < 0.001) and octoploid (0.1-16.1%; p < 0.001) populations, and a noticeable decrease in diploid hepatocytes (92.9-34.3%; p < 0.001), were observed. Populations involved in 2C-->4C DNA synthesis decreased from 3.6 to 0.9% (p < 0.001), while those involved in 4C-->8C increased from 0.9% to 5.2% (p < 0.001). A hypodiploid population (apoptotic cells) was detected from 12 months, increasing thereafter. CONCLUSIONS: These results show that the antioxidant cell defense system increases with age but the rate of reactive oxygen species generation exceeds the induced antioxidant ability, generating a situation that favors oxidative stress and peroxidation. The progressive polyploidization is accompanied by changes in the proliferative potential that decreases from 2C to 4C and increased from 4C to 8C. The relationship between the modifications of the oxidant/antioxidant system and increased polyploidy is not clear and may be interpreted as two independent manifestations of the aging process.

J Hepatol. 1997 Sep;27(3):525-34

Lipid peroxidation and antioxidant status in experimental animals: effects of aging and hypercholesterolemic diet.

Effects of aging and hypercholesterolemic diet on lipid peroxidation and antioxidant status were investigated in rats. The rats were divided into four groups of ten: Group I; young rats receiving standard lab chow; Group II; young rats on hypercholesterolemic diet (0.4 g/rat/day); Group III; aged rates receiving standard lab chow; Group IV; aged rats on hypercholesterolemic diet (0.4 g/rat/day). Plasma lipid peroxidation end product level was determined as thiobarbutiric acid reactive substances (TBARS). Plasma cholesterol concentration was analyzed by a kinetic enzymatic method. Erythrocyte superoxide dismutase (CuZn SOD), glutathione peroxidase (GSH Px) and glutathione (GSH) levels were determined spectrophotometrically. Cholesterol values were found to be significantly high (p < 0.001), TBARS (0.05 > p > 0.02) and GSH (p < 0.001) levels significantly low in aged rats in comparison with young rats. Hypercholesterolemic diet induced significant increases in GSH (p < 0.001) and CuZn SOD (p < 0.001) levels, whereas a significant decrease in GSH Px activity (0.05 > p > 0.02) was observed in aged rats. In young rats hypercholesterolemic diet caused a significant increase in both GSH and CuZnSOD levels. Our results indicate an imbalance between radical production and destruction in favour of prooxidant conditions in the young rats and the induction by hypercholesterolemic diet of the antioxidative response in erythrocytes.

Clin Chim Acta. 1997 Sep 8;265(1):77-84

Mitochondrial abnormalities in muscle and other aging cells: classification, causes, and effects.

The involvement of mitochondria and of mitochondrial DNA (mtDNA) in the aging process has generated much interest and even more controversy. The mitochondrial theory of aging considers a vicious circle consisting of: (1) accumulation of somatic mtDNA mutations; (2) impairment of respiratory chain function; (3) increased production of reactive oxygen species (ROS) in mitochondria; and (4) further damage to mtDNA. We review the evidence for and against the belief that these steps occur in aging muscle and brain, considering separately morphological, biochemical, and molecular data. The relationship between mitochondrial aging and late-onset neurodegenerative diseases is briefly reviewed. We conclude that mitochondrial dysfunction does play a crucial role in the aging process of both muscle and brain, but it remains unclear whether mitochondria are the culprits or mere accomplices.

Muscle Nerve. 2002 Nov;26(5):597-607

Mitochondrial aging and dysfunction in Alzheimer’s disease.

Disruptions in energy metabolism have been suggested to be a prominent feature, perhaps even a fundamental component, of Alzheimer’s disease (AD). These abnormalities in cerebral metabolism precede the onset of neurological dysfunction as well as gross neuropathology of AD. These changes may stem from inhibition of mitochondrial enzymes including pyruvate dehydrogenase, cytochrome c oxidase, and alpha-ketoglutarate dehydrogenase. Several lines of evidence also suggest a role for oxidative stress in the neuropathology associated with the disease state. Because mitochondria are the major site of free radical production in cells, they are also a primary target for oxidative damage and subsequent dysfunction. This link between mitochondrial dysfunction and the pathophysiology of AD is supported by several lines of evidence.

Prog Neuropsychopharmacol Biol Psychiatry. 2005 Mar;29(3):407-10

A detailed safety assessment of a saw palmetto extract.

BACKGROUND: Saw palmetto is commonly used by men for lower-urinary tract symptoms. Despite its widespread use, very little is known about the potential toxicity of this dietary supplement. METHODS: The Saw palmetto for Treatment of Enlarged Prostates (STEP) study was a randomized clinical trial performed among 225 men with moderate-to-severe symptoms of benign prostatic hyperplasia, comparing a standardized extract of the saw palmetto berry (160 mg twice daily) with a placebo over a 1-year period. As part of this study, detailed data were collected on serious and non-serious adverse events, sexual functioning, and laboratory tests of blood and urine. Between-group differences were assessed with mixed-effects regression models. RESULTS: There were no significant differences observed between the saw palmetto and placebo-allocated participants in the risk of suffering at least one serious adverse event (5.4% vs. 9.7%, respectively; p=0.31) or non-serious symptomatic adverse event (34.8% vs. 30.1%, p=0.48). There were few significant between-group differences in sexual functioning or for most laboratory analyses, with only small differences observed in changes over time in total bilirubin (p=0.001), potassium (p=0.03), and the incidence of glycosuria (0% in the saw palmetto group vs. 3.7% in the placebo group, p=0.05). CONCLUSIONS: Despite careful assessment, no evidence for serious toxicity of saw palmetto was observed in this clinical trial. Given the sample size and length of this study, however, these data do not rule out potential rare adverse effects associated with the use of saw palmetto.

Complement Ther Med. 2008 Jun;16(3):147-54

Saw Palmetto induces growth arrest and apoptosis of androgen-dependent prostate cancer LNCaP cells via inactivation of STAT 3 and androgen receptor signaling.

PC-SPES is an eight-herb mixture that has an activity against prostate cancer. Recently, we purified Saw Palmetto (Serenoa repens) from PC-SPES and found that Saw Palmetto induced growth arrest of prostate cancer LNCaP, DU145, and PC3 cells with ED50s of approximately 2.0, 2.6, and 3.3 microl/ml, respectively, as measured by mitochondrial-dependent conversion of the the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Saw Palmetto induced apoptosis of LNCaP cells in a time- and dose-dependent manner as measured by TUNEL assays. Also, Saw Palmetto increased the expression of p21waf1 and p53 protein in LNCaP cells. In addition, we found that Saw Palmetto down-regulated DHT- or IL-6-induced expression of prostate specific antigen in conjunction with down-regulation of the level of androgen receptor in the nucleus as measured by Western blot analysis. Moreover, Saw Palmetto down-regulated the IL-6-induced level of the phosphorylated form of STAT 3 in LNCaP cells. Furthermore, Saw Palmetto inhibited the growth of LNCaP cells present as tumor xenografts in BALB/c nude mice without adverse effect. These results indicate that Saw Palmetto might be useful for the treatment of individuals with prostate cancer.

Int J Oncol. 2007 Sep;31(3):593-600

Effects of dietary saw palmetto on the prostate of transgenic adenocarcinoma of the mouse prostate model (TRAMP).

BACKGROUND: Several of the proposed mechanisms for the actions of the liposterolic extract of saw palmetto (SPE) are exerted on known risk factors for prostate cancer (CaP). This study investigated whether SPE could prevent the progression of CaP in a transgenic adenocarcinoma of the mouse prostate (TRAMP) model. METHODS: Two different doses of SPE designed to deliver 50 mg/kg/day SPE and 300 mg/kg/day SPE were administered in a custom diet to TRAMP mice for 12 or 24 weeks. Body and organ weights were used to evaluate toxicity, and radioimmunoassay was used to measure plasma and tissue androgen levels to monitor effects of SPE on 5alpha reductase activity. Prostate tissues were evaluated histologically to determine the effect of treatment on tumor grade, cell proliferation, and apoptosis. RESULTS: Treatment with 300 mg/kg/day SPE from 4 to 24 weeks of age significantly reduced the concentration of 5alpha-dihydrotestosterone (DHT) in the prostate and resulted in a significant increase in apoptosis and significant decrease in pathological tumor grade and frank tumor incidence. CONCLUSIONS: Dietary supplementation with SPE may be effective in controlling CaP tumorigenesis. SPE suppression of prostatic DHT levels lends support to the hypothesis that inhibition of the enzyme 5alpha-reductase is a mechanism of action of this substance.

Prostate. 2007 May 1;67(6):661-73

A preliminary investigation of the enzymatic inhibition of 5alpha-reduction and growth of prostatic carcinoma cell line LNCap-FGC by natural astaxanthin and Saw Palmetto lipid extract in vitro.

Inhibition of 5alpha-reductase has been reported to decrease the symptoms of benign prostate hyperplasia (BPH) and possibly inhibit or help treat prostate cancer. Saw Palmetto berry lipid extract (SPLE) is reported to inhibit 5alpha-reductase and decrease the clinical symptoms of BPH. Epidemiologic studies report that carotenoids such as lycopene may inhibit prostate cancer. In this investigation the effect of the carotenoid astaxanthin, and SPLE were examined for their effect on 5alpha-reductase inhibition as well as the growth of prostatic carcinoma cells in vitro. These studies support patent #6,277,417 B1. The results show astaxanthin demonstrated 98% inhibition of 5alpha-reductase at 300 microg/mL in vitro. Alphastat, the combination of astaxanthin and SPLE, showed a 20% greater inhibition of 5alpha-reductase than SPLE alone n vitro. A nine day treatment of prostatic carcinoma cells with astaxanthin in vitro produced a 24% decrease in growth at 0.1 mcg/mL and a 38% decrease at 0.01 mcg/mL. SPLE showed a 34% decrease at 0.1 mcg/mL. CONCLUSIONS: Low levels of carotenoid astaxanthin inhibit 5alpha-reductase and decrease the growth of human prostatic cancer cells in vitro. Astaxanthin added to SPLE shows greater inhibition of 5alpha-reductase than SPLE alone in vitro.

J Herb Pharmacother. 2005;5(1):17-26

Saw palmetto for the treatment of men with lower urinary tract symptoms.

PURPOSE: A comprehensive review of the literature on the use of saw palmetto in men with lower urinary tract symptoms is provided. MATERIALS AND METHODS: A literature search of studies that have assessed the mechanism of action and clinical results of saw palmetto in men with benign prostatic hyperplasia was performed. RESULTS: A variety of potential mechanisms of action of saw palmetto have been demonstrated through in vitro studies, including 5-alpha reductase inhibition, adrenergic receptor antagonism and intraprostatic androgen receptor blockade. Clinical evidence of the relevance of these effects is largely unavailable. The use of saw palmetto in men with benign prostatic hyperplasia is safe with no recognized adverse effects. No effect on serum prostate specific antigen has been noted. Placebo controlled trials and meta-analyses have suggested that saw palmetto leads to subjective and objective improvement in men with lower urinary tract symptoms. However, most studies are significantly limited by methodological flaws, small patient numbers and brief treatment intervals. CONCLUSIONS: Evidence suggests that saw palmetto may have a significant effect on urinary flow rates and symptom scores compared to placebo in men with lower urinary tract symptoms. However, large scale, placebo controlled trials are needed to assess the efficacy of saw palmetto.

J Urol. 2000 May;163(5):1408-12

Phytotherapy for benign prostatic hyperplasia.

OBJECTIVE: To systematically review the existing evidence regarding the efficacy and safety of phytotherapeutic compounds used to treat men with symptomatic benign prostatic hyperplasia (BPH). DESIGN: Randomized trials were identified searching MEDLINE (1966--1997), EMBASE, Phytodok, the Cochrane Library, bibliographies of identified trials and review articles, and contact with relevant authors and drug companies. The studies were included if men had symptomatic benign prostatic hyperplasia, the intervention was a phytotherapeutic preparation alone or combined, a control group received placebo or other pharmacologic therapies for BPH, and the treatment duration was at least 30 days. Key data were extracted independently by two investigators. RESULTS: A total of 44 studies of six phytotherapeutic agents (Serenoa repens, Hypoxis rooperi, Secale cereale, Pygeum africanum, Urtica dioica, Curcubita pepo) met inclusion criteria and were reviewed. Many studies did not report results in a method allowing meta-analysis. Serenoa repens, extracted from the saw palmetto, is the most widely used phytotherapeutic agent for BPH. A total of 18 trials involving 2939 men were reviewed. Compared with men receiving placebo, men taking Serenoa repens reported greater improvement of urinary tract symptoms and flow measures. Serenoa repens decreased nocturia (weighted mean difference (WMD) = -0.76 times per evening; 95% CI = -1.22 to -0.32; n = 10 studies) and improved peak urine flow (WMD = 1.93 ml s(-1); 95% CI = 0.72 to 3.14, n = 8 studies). Men treated with Serenoa repens rated greater improvement of their urinary tract symptoms versus men taking placebo (risk ratio of improvement = 1.72; 95% CI = 1.21 to 2.44, n = 8 studies). Improvement in symptoms of BPH was comparable to men receiving the finasteride. Hypoxis rooperi (n = 4 studies, 519 men) was also demonstrated to be effective in improving symptom scores and flow measures compared with placebo. For the two studies reporting the International Prostate Symptom Score, the WMD was -4.9 IPSS points (95% CI = -6.3 to -3.5, n = 2 studies) and the WMD for peak urine flow was 3.91 ml s(-1) (95% CI = 0.91 to 6.90, n = 4 studies). Secale cereale (n = 4 studies, 444 men) was found to modestly improve overall urological symptoms. Pygeum africanum (n = 17 studies, 900 men) may be a useful treatment option for BPH. However, review of the literature has found inadequate reporting of outcomes which currently limit the ability to estimate its safety and efficacy. The studies involving Urtica dioica and Curcubita pepo are limited although these agents may be effective combined with other plant extracts such as Serenoa and Pygeum. Adverse events due to phytotherapies were reported to be generally mild and infrequent. CONCLUSIONS: Randomized studies of Serenoa repens, alone or in combination with other plant extracts, have provided the strongest evidence for efficacy and tolerability in treatment of BPH in comparison with other phytotherapies. Serenoa repens appears to be a useful option for improving lower urinary tract symptoms and flow measures. Hypoxis rooperi and Secale cereale also appear to improve BPH symptoms although the evidence is less strong for these products. Pygeum africanum has been studied extensively but inadequate reporting of outcomes limits the ability to conclusively recommend it. There is no convincing evidence supporting the use of Urtica dioica or Curcubita pepo alone for treatment of BPH. Overall, phytotherapies are less costly, well tolerated and adverse events are generally mild and infrequent. Future randomized controlled trials using standardized preparations of phytotherapeutic agents with longer study durations are needed to determine their long-term effectiveness in the treatment of BPH.

Public Health Nutr. 2000 Dec;3(4A):459-72

Role of phytotherapy in men with lower urinary tract symptoms.

PURPOSE OF REVIEW: Serenoa repens extract is a popular phytotherapeutic agent in men with lower urinary tract symptoms. Although the exact mechanism of action is unknown, the agent is generally well accepted for its easy availability and good tolerability. This paper reviews the evidence of its efficacy in comparison with placebo, 5-alpha reductase inhibitor and alpha-1 adrenoreceptor antagonist. RECENT FINDINGS: Serenoa repens extract is comparable with 5-alpha reductase (finasteride) and alpha-1 antagonist in the treatment of benign prostatic hyperplasia in terms of symptom score and peak urinary flow rate improvement, but has a lower incidence of associated sexual dysfunction. Furthermore, long-term usage (36 months) of Serenoa repens decreases the progression rate of the condition as compared with watchful waiting. In addition, the efficacies of Serenoa repens are proven in several placebo-controlled trials. SUMMARY: Serenoa repens has proven its role in the management of benign prostatic hyperplasia and will remain as a viable first-line treatment option.

Curr Opin Urol. 2005 Jan;15(1):45-8

Efficacy and safety of a combination of sabal and urtica extract in lower urinary tract symptoms. A randomized, double-blind study versus tamsulosin.

The aim of this prospective, randomized, double-blind, double-dummy, multicenter clinical trial was to investigate the efficacy and safety of PRO 160/120 (Prostagutt forte), a fixed combination preparation of 160 mg Sabal fruit extract WS 1473 and 120 mg Urtica root extract WS 1031 per capsule, in comparison to the alpha1-adrenoceptor antagonist tamsulosin (CAS 106463-17-6) in lower urinary tract symptoms (LUTS) caused by benign prostatic hyperplasia (BPH). 140 elderly out-patients suffering from LUTS caused by BPH, with an initial score > or = 13 points in the International Prostate Symptom Score (I-PSS), received 2 x 1 capsule/d PRO 160/120 or 1 x 0.4 mg/d tamsulosin and were treated for 60 weeks with interim visits at weeks 8, 16, 24, 36, and 48. The primary outcome measure for efficacy was the change in I-PSS total score, the percentage of patients with an I-PSS score < or = 7 points at endpoint (‘responders’) was analyzed as well. During 60 weeks of randomized treatment the I-PSS total score was reduced by a median of 9 points in both groups. In total, 32.4 % of the patients in the PRO 160/120 group and 27.9% in the tamsulosin group were responders (test for non-inferiority of PRO 160/120: p = 0.034; non-inferiority margin 10%). Both drugs were well tolerated, with one adverse event in 1514 treatment days for PRO 160/120 and one event in 1164 days for tamsulosin. The study supports non-inferiority of PRO 160/120 in comparison to tamsulosin in the treatment of LUTS caused by BPH.

Arzneimittelforschung. 2006;56(3):222-9

Serenoa repens (Permixon) inhibits the 5alpha-reductase activity of human prostate cancer cell lines without interfering with PSA expression.

The phytotherapeutic agent Serenoa repens is an effective dual inhibitor of 5alpha-reductase isoenzyme activity in the prostate. Unlike other 5alpha-reductase inhibitors, Serenoa repens induces its effects without interfering with the cellular capacity to secrete PSA. Here, we focussed on the possible pathways that might differentiate the action of Permixon from that of synthetic 5alpha-reductase inhibitors. We demonstrate that Serenoa repens, unlike other 5alpha-reductase inhibitors, does not inhibit binding between activated AR and the steroid receptor-binding consensus in the promoter region of the PSA gene. This was shown by a combination of techniques: assessment of the effect of Permixon on androgen action in the LNCaP prostate cancer cell line revealed no suppression of AR and maintenance of PSA protein expression at control levels. This was consistent with reporter gene experiments showing that Permixon failed to interfere with AR-mediated transcriptional activation of PSA and that both testosterone and DHT were equally effective at maintaining this activity. Our results demonstrate that despite Serenoa repens effective inhibition of 5alpha-reductase activity in the prostate, it did not suppress PSA secretion. Therefore, we confirm the therapeutic advantage of Serenoa repens over other 5alpha-reductase inhibitors as treatment with the phytotherapeutic agent will permit the continuous use of PSA measurements as a useful biomarker for prostate cancer screening and for evaluating tumour progression.

Int J Cancer. 2005 Mar 20;114(2):190-4

Serenoa repens extract targets mitochondria and activates the intrinsic apoptotic pathway in human prostate cancer cells.

OBJECTIVE: To investigate the effects of Serenoa repens extract (Sr) in human PC3 and LNCaP prostate cancer and MCF7 breast cancer cells, with specific emphasis on the role of the mitochondrial apoptotic pathway, as the molecular pathway through which Sr, a natural product of plant origin, induces death of prostate cancer cells in culture is still unknown. MATERIAL AND METHODS: Cellular and mitochondrial structure and function, and the cell cycle, were analysed using light, electron and fluorescence microscopy, spectrophotometry and flow cytometry. Apoptosis was evaluated using biochemical and cytohistochemical methods. RESULTS: Cells treated with Sr underwent massive vacuolization and cytosolic condensation, followed by cell death only in the prostate lines. Within minutes of adding Sr to prostate cells, it caused opening of the permeability transition pore (PTP), which led to complete mitochondrial depolarization within 2 h, and to the appearance of small, pycnotic mitochondria. Release of cytochrome c and SMAC/Diablo to the cytosol was detectable after 4 h of treatment, while caspase 9 activation and poly(ADP-ribose) polymerase 1 cleavage occurred at 16 h, followed by appearance of a sub-G1 peak and apoptosis at 24 h. CONCLUSION: Sr selectively induces apoptotic cell death of prostate cancer cells through the intrinsic pathway, and activation of the mitochondrial PTP might play a central role in this process.

BJU Int. 2009 May;103(9):1275-83

Feeding tomato and broccoli powders enriched with bioactives improves bioactivity markers in rats.

Many studies have evaluated the cancer -preventive potential of individual bioactives from tomatoes and broccoli, but few have examined them within the context of a whole food. Male Copenhagen rats were fed diets containing 10% standard tomato powder, tomato enriched with lycopene or total carotenoids, standard broccoli floret, broccoli sprouts, or broccoli enriched with indole glucosinolates or selenium for 7 days. All broccoli diets increased the activity of colon quinone reductase (NQO1). Indole glucosinolate-enriched broccoli and selenium-enriched broccoli increased hepatic NQO1 and cytochrome P450 1A activity (P < 0.05). Standard broccoli and lycopene-enriched tomato diets down-regulated prostatic glutathione S-transferase P1 mRNA expression. Different tomato diets resulted in altered hepatic accumulation of lycopene, phytofluene, and phytoene. These results demonstrate that the bioactive content of vegetables affects both tissue content of bioactives and activity of detoxification enzymes. Enhancing bioactive content of tomatoes and broccoli may enhance efficacy in the prevention of prostate cancer.

J Agric Food Chem. 2009 Aug 3

Economic evaluation of medical treatment of benign prostatic hyperplasia (BPH) in the specialised care setting in Spain. Application to the cost-effectiveness of two drugs frequently used in its treatment.

OBJECTIVES: To develop a pharmacoeconomic study in order to know the average cost of BPH diagnosis and follow-up in Spain in the Urology Department setting from the perspective of the public health system, considering two frequently used drugs in the Spanish Healthcare environment, an alpha-blocker (tamsulosin) and the lipido-sterolic extract of Serenoa repens (Permixon). MATERIAL AND METHODS: Direct healthcare costs of BPH diagnosis and treatment were determined for each clinical stage according to the International Prostate Symptom Score (IPSS): mild, moderate and severe. Data on the usage and unit costs of healthcare resources were obtained from a semi-structured interview with clinical experts. The clinical efficacy of the medical treatments was obtained from the PERMAL clinical study, where therapeutic equivalence between the two studied drugs was observed. RESULTS: For patients treated in the Urology Department setting, the average annual cost of diagnostic tests and medical visits related to mild, moderate or severe BPH symptoms were, respectively, Euro 124, Euro 207, and Euro 286. The average annual cost of the drugs, including adverse effects treatment, was Euro 211 for Permixon and Euro 346 for tamsulosin. DISCUSSION: Costs of medical care of BPH increases with symptom intensity. Pharmacological treatment makes up a significant part of the disease’s cost. According to the model used, treatment with Permixon is considerably more cost-effective than with tamsulosin, offering average yearly savings of Euro 135 per patient.

Actas Urol Esp. 2008 Oct;32(9):916-25